Optical fiber cable

ABSTRACT

An optical fiber cable having excellent workability and long-term reliability. The cable comprises at least one optical fiber, a plastic jacket covering the optical fiber or optical fibers, and at least one anti-shrink member embedded in the jacket. The jacket has a longitudinal shrinkage of at most 0.5% when heated at 110° C. for two hours. The cable has a remaining bend with a radius of curvature of at least 100 mm when wound on a 50-mm-radious mandrel and heated at 85° C. for two hours. The deflection of a 30-cm-long cantilever made of the cable is at least 50 mm. In one aspect of the cable, the cable is specified by the conditions of ES t /ES j ≧0.7, EI t /EI c ≧0.1, and EI c /M c ≦8×10 6  mm 3  (E: Young&#39;s modulus; S: cross-sectional area; t: total of anti-shrink members; j: jacket; I: geometrical moment of inertia; c: cable; and M: mass).

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates generally to an optical fiber cablefor use mainly in indoor wiring, and particularly to an optical fibercable provided with at least one anti-shrink member and a plasticjacket.

[0003] 2. Description of the Background Art

[0004] An optical fiber cable for use in indoor wiring usually has astructure in which tension members are placed around a plurality ofoptical fibers, and a plastic jacket is provided as an outer covering.It is usual that the jacket shrinks longitudinally with time due toresidual stresses produced during the covering process. When thelongitudinal shrinkage of the jacket is large, stresses are applied tothe optical fibers. The stresses may affect the transmission propertiesof the optical fibers.

[0005] To suppress the shrinkage of the jacket, researchers andengineers have been studying a structure in which anti-shrink membersare embedded in the jacket. On the other hand, as multi-fiber connectorsare widely used for connecting a plurality of optical fibers as oneunit, optical transmission lines frequently use optical fiber cableshaving a fiber ribbon, in which multiple optical fibers are organized ina flat array. Japanese patent 2793621 has disclosed a structure in whicha fiber ribbon is enclosed by a jacket in which tension members areembedded. The tension members also function as anti-shrink members forsuppressing the longitudinal shrinkage of the jacket.

SUMMARY OF THE INVENTION

[0006] An object of the present invention is to solve theabove-described problem and to offer an optical fiber cable havingexcellent workability and long-term reliability.

[0007] According to the present invention, the foregoing and otherobjects and advantages are attained by offering an optical fiber cabledescribed below. The optical fiber cable comprises the followingcomponents:

[0008] (a) at least one optical fiber;

[0009] (b) a plastic jacket covering the optical fiber or opticalfibers; and

[0010] (c) at least one anti-shrink member that is embedded in thejacket and that is intended to suppress the longitudinal shrink of thejacket.

[0011] In this cable, the jacket has the property that the longitudinalshrinkage is at most 0.5% when a sample of the jacket including theanti-shrink member or members but excluding the optical fiber or fibersis heated at 110° C. for two hours. The optical fiber cable has thefollowing properties:

[0012] (a) The remaining bend of the cable has a radius of curvature ofat least 100 mm when a sample of the cable is wound on a mandrel havinga radius of 50 mm, is secured there, is heated at 85° C. for two hours,and then is unwound from the mandrel.

[0013] (b) The deflection at the free end of a cantilever is at least 50mm when the cantilever is formed by using a sample of the cable having alength of 30 cm and when the deflection is obtained by averaging themaximum deflection and the minimum deflection. In this case, the valueof the maximum deflection is obtained by turning the cable sample aroundits own axis to find the position where the deflection at the free endis maximized due to the bending tendency of the cable sample. The valueof the minimum deflection is obtained by turning the cable sample againaround its own axis to find the position where the deflection at thefree end is minimized due to the bending tendency.

[0014] In accordance with one aspect of the invention, the optical fibercable has the following properties:

[0015] (a) The ratio ES_(t)/ES_(j) is at least 0.7, where ES_(t) denotesthe product of the Young's modulus and cross-sectional area of theanti-shrink member or the total value of the products of the Young'smodulus and cross-sectional area of the anti-shrink members, and ES_(j)denotes the product of the Young's modulus and cross-sectional area ofthe entire jacket including the anti-shrink member or members;

[0016] (b) The ratio EI_(t)/EI_(c) is at least 0.1, where EI_(t) denotesthe flexural rigidity of the anti-shrink member or the total value ofthe flexural rigidities of the anti-shrink members (the flexuralrigidity is expressed by the product of the Young's modulus and thegeometrical moment of inertia), and EI_(c) denotes the flexural rigidityof the entire cable.

[0017] (c) The ratio EI_(c)/M_(c) is at most 8×10⁶ mm³, where El_(c)denotes the flexural rigidity of the entire cable, and M_(c) denotes themass per unit length of the cable.

[0018] The optical fiber cable may have the dimensional relationshipexpressed as

T _(t) ≦T _(o)+0.2(mm),

[0019] where T_(t) is the total thickness of the jacket at the portionwhere the anti-shrink member or members are embedded, and T_(o) is thethickness of the jacket at the portion where no anti-shrink member isembedded.

[0020] In the optical fiber cable, the anti-shrink member or members maybe coated with a bonding material by baking. In this case, the bondingmaterial may have a thickness of at most 50 μm. The bonding materialbefore being applied onto the anti-shrink member or members may becomposed of an acrylic-resin-family bonding material dispersed in asolvent.

[0021] The optical fiber cable may further comprise a tension membersurrounding the optical fiber or fibers and being surrounded by thejacket.

[0022] In the optical fiber cable, the jacket may be made of polyvinylchloride (PVC), and the anti-shrink member or members may be made ofglass-fiber-reinforced plastic (G-FRP).

[0023] The present invention is further explained below by referring tothe accompanying drawings. The drawings are provided solely for thepurpose of illustration and are not intended to limit the scope of theinvention.

BRIEF DESCRIPTION OF THE DRAWING

[0024]FIG. 1 is a cross-sectional view showing an embodiment of theoptical fiber cable of the present invention.

[0025]FIG. 2 is a cross-sectional view showing another embodiment of theoptical fiber cable of the present invention.

[0026]FIG. 3 is a cross-sectional view showing yet another embodiment ofthe optical fiber cable of the present invention.

[0027]FIG. 4 is a graph showing the relationship between thelongitudinal shrinkage of the jacket and a parameter expressing thestructure of the optical fiber cable.

[0028]FIG. 5 is a graph showing the relationship between the remainingmagnitude of bend of the cable and another parameter expressing thestructure of the optical fiber cable.

[0029]FIG. 6 is a graph showing the relationship between the deflectionof the cable and yet another parameter expressing the structure of theoptical fiber cable.

DETAILED DESCRIPTION OF THE INVENTION

[0030] Embodiments of the present invention are explained below byreferring to the accompanying drawings. In the drawings, the same numberrefers to the same part to avoid duplicated explanation. The ratios ofthe dimensions in the drawings do not necessarily coincide with theexplanation.

[0031] It is important for an optical fiber cable for indoor-wiring useto have good workability at the time of installation and long-termreliability after the installation. When anti-shrink members areembedded in the jacket of a conventional optical fiber cable, theanti-shrink members increase the stiffness of the cable. As a result,the cable becomes difficult to bend, which means the cable has poorworkability.

[0032] Optical fiber cables for indoor-wiring use are also required tohave flame retardancy. To meet this requirement, the jacket is usuallymade of a material having high flame retardancy, such as polyvinylchloride (PVC). Such a material usually has a poor property in bondingwith the anti-shrink members. Consequently, slippage between the jacketand the anti-shrink members tends to occur. Even when the anti-shrinkmembers have high stiffness, they may not suppress the longitudinalshrinkage of the jacket. Therefore, the long-term reliability isinsufficient. To increase the bonding strength between the jacket andthe anti-shrink members, the anti-shrink members can be coated with abonding material having a good property in bonding with the jacket. Inthis case, the layer of the bonding material unavoidably increases thetotal thickness of the jacket, and it is difficult to find a materialthat has both a good property in bonding with the jacket and high flameretardancy.

[0033]FIG. 1 is a cross-sectional view showing an embodiment of theoptical fiber cable of the present invention. In this embodiment, aplurality of optical fibers 1 coated with ultraviolet (UV)-cured resinare organized in a flat array. The array is consolidated by applyinganother coating of UV-cured resin around the array to form a fiberribbon 2. The fiber ribbon 2 is surrounded by a tension member 3 made ofaramid fiber. The tension member 3 is covered with a jacket 4, in whichanti-shrink members 5 are embedded at the outside of the outermostfibers in the array.

[0034]FIG. 2 is a cross-sectional view showing another embodiment of theoptical fiber cable of the present invention. In this embodiment, theanti-shrink members 5 are coated with a bonding-material layer 6.

[0035]FIG. 3 is a cross-sectional view showing yet another embodiment ofthe optical fiber cable of the present invention. In this embodiment, afiber ribbon 2 is surrounded by an approximately circular tension member3 made of aramid fiber. The tension member 3 is covered with a jacket 4,in which two anti-shrink members 5 are embedded at the outside of eachof the outermost fibers in the array. As shown in this embodiment, thepresent invention can be applied to a cable having a circular crosssection. More specifically, the present invention can be applied notonly to a cable having a fiber ribbon but also to a cable havingmultiple optical fibers stranded together to form a circular crosssection. This embodiment also shows that a plurality of anti-shrinkmembers may be provided at the outside of each of the outermost fibersin the array.

[0036] Although the optical fiber cables shown in FIGS. 1 to 3 use aplurality of anti-shrink members 5, an optical fiber cable may use oneanti-shrink member when a plurality of anti-shrink members are notrequired.

[0037] Various optical fiber cables having the structure shown in FIG. 1were produced by changing the size of the anti-shrink members 5 to studythe relationship between the size of the anti-shrink members 5 and theproperties of the cable. The jacket 4 was made of PVC (brand name: APCOR2002). The anti-shrink members 5 were made of glass-fiber-reinforcedplastic (G-FRP). The cable had an overall width of 4.8 mm and an overallthickness of 2.4 mm. The jacket 4 had a thickness of 0.5 mm at about themidpoint position of the cable's width.

[0038] First, a study was conducted to evaluate the shrinking propertyof the cable. The longitudinal shrinkage was measured by the followingsteps:

[0039] (a) The optical fibers and the aramid fiber were drawn out of ashort length of the cable to obtain a sample of the jacket including theanti-shrink members.

[0040] (b) The sample was cut to a length of 1.1 m, and two referencepoints were marked at a separation of 1 m.

[0041] (c) The sample was placed on a layer of talc laid in a containerand heated at 110° C. for two hours.

[0042] (d) The sample was cooled and maintained at 23° C. for one hourto measure the separation between the two reference points to obtain thelongitudinal shrinkage.

[0043] The measured results are shown in FIG. 4. In FIG. 4, the abscissaof the graph represents the ratio ES_(t)/ES_(j). Here, ES_(t) denotesthe total value of the products of the Young's modulus andcross-sectional area of the anti-shrink members, and ES_(j) denotes theproduct of the Young's modulus and cross-sectional area of the entirejacket including the anti-shrink members. As shown in the graph, whenthe diameter of the anti-shrink members 5 is 0.21 mm, the longitudinalshrinkage is less than 0.5%, and when the diameter is 0.1 mm, thelongitudinal shrinkage is about 1%. In other words, when the anti-shrinkmembers 5 have a large size to a certain extent, the anti-shrink members5 overcome the stress acting to shrink the jacket longitudinally withtime, enabling the suppression of the shrink. It is required to reducethe longitudinal shrinkage to at most 0.5% to prevent the shrink of thejacket from deteriorating the cable properties. According to FIG. 4,this requirement can be met when the ratio ES_(t)/ES_(j) is increased toat least 0.7.

[0044] Second, another study was conducted to obtain the relationshipbetween the size of the anti-shrink members 5 and the bending tendencyof the cable. The relationship was obtained by the following steps:

[0045] (a) A sample of the optical fiber cable having a length of 30 cmwas wound on a mandrel having a radius of 50 mm to be secured there witha length of glass tape.

[0046] (b) The sample cable was heated at 85° C. for two hours.

[0047] (c) The sample cable was unwound from the mandrel.

[0048] (d) The sample cable was hung vertically to measure the radius ofcurvature of a bending portion remaining at the lower end portion of thecable.

[0049] The measured results are shown in FIG. 5. In FIG. 5, the abscissaof the graph represents the ratio EI_(t)/EI_(c). Here, EI_(t) denotesthe total value of the flexural rigidities of the anti-shrink members(the flexural rigidity is expressed by the product of the Young'smodulus and the geometrical moment of inertia), and EI_(c) denotes theflexural rigidity of the entire cable. As shown in the graph, when theratio EI_(t)/EI_(c) increases, and as the total value of the flexuralrigidities of the anti-shrink members comes to govern the flexuralrigidity of the entire cable, the radius of curvature increases. It isrequired to increase the radius of curvature to at least 100 mm for thebending tendency of the cable to be allowed. According to FIG. 5, thisrequirement can be met when the ratio EI_(t)/EI_(c) is increased to atleast 0.1.

[0050] Third, yet another study was conducted to evaluate theflexibility of the cable. The flexibility was evaluated by measuring theamount of deflection when one end of a sample cable was supported toform a cantilever. Considering the inevitable bending tendency givenduring the cable production, the amount of deflection was measured bythe following steps:

[0051] (a) A reference mark was provided at a portion 30 cm away fromone end of a sample cable.

[0052] (b) The sample cable was supported horizontally at the markedportion to form a cantilever. The cable was turned around its own axisto find the position where the deflection at the other end is maximizeddue to the bending tendency. Then, the maximum deflection was measured.

[0053] (c) The cable was again turned around its own axis to find theposition where the deflection at the other end is minimized due to thebending tendency. Then, the minimum deflection was measured.

[0054] (d) The measured values of the maximum and minimum deflectionswere averaged.

[0055] The measured results are shown in FIG. 6. In FIG. 6, the abscissaof the graph represents the ratio EI_(c)/M_(c). Here, EI_(c) denotes theflexural rigidity of the cable, and M_(c) denotes the mass per unitlength of the cable. As shown in the graph, as the ratio EI_(c)/M_(c)decreases, the deflection increases. It is required to increase thedeflection to at least 50 mm to obtain a cable having good flexibilityand excellent workability. According to FIG. 6, this requirement can bemet when the ratio EI_(c)/M_(c) is decreased to at most 8×10⁶ mm³.

[0056] As described above, the optical fiber cable of the presentinvention can not only suppress the longitudinal shrink of the jacketand have superior long-term reliability but also have excellentworkability because of its reduced bending tendency and goodflexibility.

[0057] The optical fiber cable of the present invention can be producedby using the materials described below. The anti-shrink members 5 may becomposed of a material such as a steel wire, fiber-reinforced plastic(FRP), or polyester yarn. Of these materials, it is desirable to useglass-fiber-reinforced plastic (G-FRP) because it has proper compressionstrength and stiffness. It is desirable that the anti-shrink members 5composed of G-FRP have a minimal diameter considering the space to beembedded in the jacket 4. However, it is required that the diameter beat least 0.2 mm in order to withstand the longitudinal shrink of thejacket 4. On the other hand, it is desirable that the diameter be atmost 0.9 mm to secure proper flexibility. Therefore, it is desirablethat the anti-shrink members 5 have a diameter of 0.2 to 0.9 mm. It isalso desirable that the jacket have the following dimensionalrelationship:

T _(t) ≦T _(o)+0.2(mm),

[0058] where T_(t) is the total thickness of the jacket at the portionwhere the anti-shrink member or members are embedded, and T_(o) is thethickness of the jacket at the portion where no anti-shrink member isembedded.

[0059] The jacket 4 may be made of thermoplastic resin such as PVC,polyethylene, fluororesin, or a polyester elastomer. Of these materials,PVC is widely used for indoor wiring because flame retardancy is one ofthe most important properties for this type of installation.

[0060] The bonding-material layer 6 for the cable shown in FIG. 2 isformed by the following process: First, the bonding material is appliedto the surface of the anti-shrink member 5. Second, the bonding materialis heated at a temperature of 100 to 300° C. to harden it. As thebonding material, it is desirable to use a material, such as acrylicresin, ethylene vinyl acetate resin, or nitrile rubber, dissolved in asolvent, such as benzene, toluene, or xylene.

[0061] The bonding material can be applied by passing the anti-shrinkmember 5 at a constant speed through a die assembly that is filled withthe bonding material dissolved in a solvent. Then, the anti-shrinkmember 5 coated with the bonding material passes through ahigh-temperature furnace to be wound on a reel. The solvent volatilizesin the high-temperature furnace at a temperature of 100 to 300° C. toform the thin bonding-material layer 6.

[0062] It is desirable that the bonding-material layer 6 have athickness of at most 50 μm. If the thickness is more than 50 μm, whenthe optical fiber cable is subjected to a combustion test, thebonding-material layer 6 readily burns, and the optical fiber cablefails to have sufficient flame retardancy.

[0063] To obtain sufficient flame retardancy and sufficient bondingstrength between the jacket 4 and the anti-shrink members 5, it isdesirable that the jacket 4 be made of PVC and that the bonding-materiallayer 6 be formed by applying and baking an acrylic-resin-family bondingmaterial dispersed in a solvent. PVC has sufficient flame retardancy andhas a comparatively good property in bonding with theacrylic-resin-family bonding material. The acrylic-resin-family bondingmaterial dispersed in a solvent can form a thin coating by volatilizingthe solvent. Therefore, even though the bonding material itself has poorflame retardancy, the bonding material has no significant effect on theoverall flame retardancy of the optical fiber cable. It is desirablethat the anti-shrink members 5 be composed of G-FRP. The plastic portionof the G-FRP can have sufficient strength in bonding with theacrylic-resin-family bonding material, and the flame retardancy can beimproved by increasing the filling density of glass fiber.

[0064] The optical fiber cable of the present invention has excellentflame retardancy and meets the requirements stipulated in theUnderwriters Laboratories (UL) Standard by showing aself-fire-extinguishing ability when tested by the UL 1666 riser testmethod.

EXAMPLE

[0065] A long optical fiber cable having the structure shown in FIG. 2was produced. Twelve single-mode optical fibers 1 coated with UV-curedresin were organized in a flat array. The array was consolidated byapplying another coating of UV-cured resin around the array to form afiber ribbon 2. The fiber ribbon 2 was surrounded by a tension member 3made of aramid fiber. The tension member 3 was covered with an extrudedPVC jacket 4, in which G-FRP anti-shrink members 5 having a diameter of0.4 mm were embedded at the outside of the outermost fibers in thearray. The anti-shrink members 5 were coated in advance with abonding-material layer 6 made of an acrylic-resin-family bondingmaterial. Thus, the optical fiber cable having the structure shown inFIG. 2 was produced. The cable had an external size of 4.8×2.4 mm, andthe jacket 4 had a thickness of 0.5 mm.

[0066] The jacket 4 was formed using PVC manufactured by APCO under abrand name of R200R. The bonding-material layer 6 having a thickness of10 μm was formed by the following process: First, acrylic resindissolved in toluene was applied to the surface of the G-FRP anti-shrinkmember 5 by using a die. Second, the toluene was volatilized by passingthe anti-shrink member 5 through a high-temperature furnace at atemperature of 200° C.

[0067] As described above, when the ratio ES_(t)/ES_(j) increases, thelongitudinal shrinkage of the cable jacket decreases. Here, ES_(t)denotes the total value of the products of the Young's modulus andcross-sectional area of the anti-shrink members, and ES_(j) denotes theproduct of the Young's modulus and cross-sectional area of the entirejacket including the anti-shrink members. With the cable of thisexample, the value of ES_(t)/ES_(j) was 0.9. According to FIG. 4, thisvalue corresponds to a longitudinal shrinkage of less than 0.5%. Thecable had a sufficiently small total flexural rigidity in comparisonwith the mass of the cable. Furthermore, the cable had a sufficientlylarge ratio of the total value of the flexural rigidities of theanti-shrink members to the flexural rigidity of the entire cable.Consequently, it was believed that the cable had excellent flexibility.

[0068] A sample of the complete jacket 4 having a length of 150 cm wassampled from the completed optical fiber cable. The sample was treatedat a temperature of 110° C. for two hours. The length of the jacketsample was measured before and after the heat treatment to obtain thevalue of the longitudinal shrinkage. The result was about 0.1%, which issufficiently small. The optical fiber cable was subjected to a handlingtest. As anticipated, the test results demonstrated that the cable waseasy to bend, which means the cable had excellent flexibility, and wasreduced in bending tendency.

[0069] The optical fiber cable was also subjected to the combustion teststipulated by the UL 1666 riser test method. The test results weresatisfactory in showing a maximum flame height of 180 cm (specifiedmaximum: 360 cm) and a maximum temperature of 218° C. (specifiedmaximum: 454° C.).

[0070] The present invention is explained mainly by referring to anoptical fiber cable having a fiber ribbon in the above description.However, the present invention can also be applied to an optical fibercable having multiple optical fibers stranded together to form acircular cross section. Furthermore, the present invention can also beapplied to an optical fiber cable having one optical fiber.

[0071] The embodiments disclosed in this specification are to beconsidered in all respects as illustrative and not restrictive. Thescope of the present invention is indicated by the following claimsrather than by the foregoing description. All changes that come withinthe meaning and range of equivalency of the claims are thereforeintended to be embraced in the scope of the present invention.

[0072] The entire disclosure of the Japanese Patent Application No.2001-320071 filed on Oct. 18, 2001 including the specification, claims,drawings, and summary is incorporated herein by reference in itsentirety.

What is claimed is:
 1. An optical fiber cable, comprising: (a) at leastone optical fiber; (b) a plastic jacket covering the optical fiber oroptical fibers; and (c) at least one anti-shrink member that: (c1) isembedded in the jacket; and (c2) is intended to suppress thelongitudinal shrink of the jacket; the jacket having the property thatthe longitudinal shrinkage is at most 0.5% when a sample of the jacketincluding the anti-shrink member or members but excluding the opticalfiber or fibers is heated at 110° C. for two hours; the optical fibercable having the properties that: (d) the remaining bend of the cablehas a radius of curvature of at least 100 mm when a sample of the cableis wound on a mandrel having a radius of 50 mm, is secured there, isheated at 85° C. for two hours, and then is unwound from the mandrel;and (e) the deflection at the free end of a cantilever is at least 50 mmwhen the cantilever is formed by using a sample of the cable having alength of 30 cm and when the deflection is obtained by averaging themaximum deflection and the minimum deflection, wherein: (e1) the valueof the maximum deflection is obtained by turning the cable sample aroundits own axis to find the position where the deflection at the free endis maximized due to the bending tendency of the cable sample; and (e2)the value of the minimum deflection is obtained by turning the cablesample again around its own axis to find the position where thedeflection at the free end is minimized due to the bending tendency. 2.An optical fiber cable, comprising: (a) at least one optical fiber; (b)a plastic jacket covering the optical fiber or optical fibers; and (c)at least one anti-shrink member that: (c1) is embedded in the jacket;and (c2) is intended to suppress the longitudinal shrink of the jacket;the optical fiber cable having the properties that: (d) the ratioES_(t)/ES_(j) is at least 0.7, where ES_(t) denotes the product of theYoung's modulus and cross-sectional area of the anti-shrink member orthe total value of the products of the Young's modulus andcross-sectional area of the anti-shrink members, and ES_(j) denotes theproduct of the Young's modulus and cross-sectional area of the entirejacket including the anti-shrink member or members; (e) the ratioEI_(t)/EI_(c) is at least 0.1, where EI_(t) denotes the flexuralrigidity of the anti-shrink member or the total value of the flexuralrigidities of the anti-shrink members (the flexural rigidity isexpressed by the product of the Young's modulus and the geometricalmoment of inertia), and EI_(c) denotes the flexural rigidity of theentire cable; and (f) the ratio EI_(c)/M_(c) is at most 8×10⁶ mm³, whereEI_(c) denotes the flexural rigidity of the entire cable, and M_(c)denotes the mass per unit length of the cable.
 3. An optical fiber cableas defined by claim 1, the optical fiber cable having the dimensionalrelationship expressed as T _(t) ≦T _(o)+0.2(mm), where T_(t) is thetotal thickness of the jacket at the portion where the anti-shrinkmember or members are embedded, and T_(o) is the thickness of the jacketat the portion where no anti-shrink member is embedded.
 4. An opticalfiber cable as defined by claim 2, the optical fiber cable having thedimensional relationship expressed as T _(t) ≦T _(o)+0.2(mm), whereT_(t) is the total thickness of the jacket at the portion where theanti-shrink member or members are embedded, and T_(o) is the thicknessof the jacket at the portion where no anti-shrink member is embedded. 5.An optical fiber cable as defined by claim 1, wherein the anti-shrinkmember or members are coated with a bonding material by baking.
 6. Anoptical fiber cable as defined by claim 2, wherein the anti-shrinkmember or members are coated with a bonding material by baking.
 7. Anoptical fiber cable as defined by claim 1, the optical fiber cablefurther comprising a tension member surrounding the optical fiber orfibers and being surrounded by the jacket.
 8. An optical fiber cable asdefined by claim 2, the optical fiber cable further comprising a tensionmember surrounding the optical fiber or fibers and being surrounded bythe jacket.
 9. An optical fiber cable as defined by claim 5, wherein thebonding material has a thickness of at most 50 μm.
 10. An optical fibercable as defined by claim 6, wherein the bonding material has athickness of at most 50 μm.
 11. An optical fiber cable as defined byclaim 5, wherein the bonding material before being applied onto theanti-shrink member or members is composed of an acrylic-resin-familybonding material dispersed in a solvent.
 12. An optical fiber cable asdefined by claim 6, wherein the bonding material before being appliedonto the anti-shrink member or members is composed of anacrylic-resin-family bonding material dispersed in a solvent.
 13. Anoptical fiber cable as defined by claim 11, wherein the jacket is madeof polyvinyl chloride.
 14. An optical fiber cable as defined by claim12, wherein the jacket is made of polyvinyl chloride.
 15. An opticalfiber cable as defined by claim 1, wherein the anti-shrink member ormembers are made of glass-fiber-reinforced plastic.
 16. An optical fibercable as defined by claim 2, wherein the anti-shrink member or membersare made of glass-fiber-reinforced plastic.
 17. An optical fiber cableas defined by claim 3, wherein the anti-shrink member or members aremade of glass-fiber-reinforced plastic.
 18. An optical fiber cable asdefined by claim 4, wherein the anti-shrink member or members are madeof glass-fiber-reinforced plastic.
 19. An optical fiber cable as definedby claim 5, wherein the anti-shrink member or members are made ofglass-fiber-reinforced plastic.
 20. An optical fiber cable as defined byclaim 6, wherein the anti-shrink member or members are made ofglass-fiber-reinforced plastic.